FR2880216A1 - Induction motor e.g. squirrel cage motor, control device, has micro-switch control unit placed between motor and neutral line and supplied electrically by electric supply unit having input connected to one of motor control lines - Google Patents

Abstract

The device has a motor (13) comprising windings (1, 2) controlled by control lines (5, 6) in respective directions. A micro-switch control unit (12) e.g. central processing unit, controls a micro-switch (8) e.g. triac, that starts or trips the motor and placed between the motor and a neutral line (11). The unit (12) is supplied electrically by an electric supply unit (7) having an input connected to one of the lines (5, 6). Independent claims are also included for the following: (A) a method for controlling an induction motor (B) a storage medium storing instructions permits to implementing a method for controlling an induction motor, when the instructions are executed by a processing unit.

Description

DEVICE AND METHOD FOR CONTROLLING A CAGE ENGINE

ELECTRONIC RACE FINS

  The present invention relates to a device and a control method for asynchronous motor with two windings, which find particular application in the control of cage motors for electronic stroke.

  Generally, the known electronic control devices and methods of such motors use automatic engine stop means which are based on the presence of a circuit breaker or switch for each winding. This circuit breaker can for example be of the micro switch type, a relay or a triac.

  With reference to FIG. 1, in most of these devices, the utility of the switches 19 and 20 for each winding 1 and 2 of the motor 13 is well understood. Indeed, these switches avoid short-circuiting the phase-shift capacitor 3. when it is necessary to control the motor in one or the other of the two directions of rotation.

  In this type of device, it is also understood that it is easy to differentiate the controls of the engine. Indeed, for example, when the switch 21 is in the position 6, the electronics of the control unit 12 (for example a conventional central processing unit, commonly called CPU) is capable, by comparison of the inputs 9 and 10, to determine the direction of rotation to be given to the motor 13, or, by combination on the inputs, to trigger various modes of operation such as for example the learning of the limit switches.

  It can also be seen that it is necessary to have a system for extracting the voltage between the points 5 (command direction 1) and 11 (neutral) or 6 (command direction 2) and 11, to provide power to the control unit 12 via a means 7 of power supply. This system may comprise, for example, a transformer or, as in FIG. 1, two capacitors 17 and 18.

  Furthermore, in this type of device, two separate sensors 15 and 16 are used to detect the direction of rotation and in particular to manage the stop at the end of the race. These sensors are for example Hall effect sensors.

  It is clear that such devices do not allow to gain size or components. The largest components are in fact the switches 19 and 20 and the supply components 17 and 18, moreover, indispensable for the operation.

  Devices such as that described in the European patent application EP 1 186 741, which propose a solution in which the two switches 19 and 20 of FIG. 1 are replaced by a single switch located between the motor and the neutral line, are also known. .

  To compensate for the absence of the switches 19 and 20 of FIG. 1 for each of the windings of the motor, the control unit is then provided to detect a possible phase shift between the voltages measured respectively at the first and second control lines of the motor (a by winding), when a voltage is actually applied to one or the other of the terminals. This phase shift is indeed due to the presence of the phase shift capacitor which connects in parallel the two windings in the motor and which participates in the power supply of the control unit. Depending on this phase shift, the motor is initially put into operation by closing, for a short time, the switch between the motor and the neutral line, it is possible to determine if the direction of rotation of the motor corresponds to the stored orders.

  However, it is actually necessary to store in advance the external commands or orders of rotation in a given direction, and to associate them with an effective direction of rotation of the motor. Insofar as detection of the phase shift is only possible when the motor is put into operation by closing, for a short period, the switch located between the motor and the neutral line, if the motor is in a very close position one end of the race, the risk exists that the engine starts abruptly and exceeds the end of stroke during the storage of an external command.

  There is therefore a need for a device and a control method for asynchronous motor with two windings, which overcomes the aforementioned drawbacks. In particular, there is a need for a device and a method that allows a reduction in size and quantity of bulky components, with a very simplified power supply, while allowing the management of external controls for rotating and stops at the end of the race without risk of damage.

  Thus, it is the object of the present invention to overcome the aforementioned drawbacks by proposing a device and a process which make it possible to gain in size and quantity of bulky component, to simplify the power supply, while reducing the risks. damage due to an inconsistency between an external control and the direction of rotation of the motor.

  The invention thus relates, in a first aspect, to a control device for asynchronous motor with two windings, in particular for an electronic end-of-stroke rolling shutter motor, in which an alternating voltage is applicable respectively to the first and second windings respectively via a first and a second control line respectively of a first and a second direction of rotation of the motor, this motor further comprising a phase shift capacitor, and this control device comprising means for switching on or off the engine located between the engine and the neutral line, and a control unit for the means for switching the engine off or on.

  The control device is characterized in that the control unit is electrically powered by a power supply means whose input is connected, via a power supply line, to only one of the first or second engine control lines.

  Preferably, the control unit comprises a means for detecting a phase shift between the voltages measured respectively at the first and second control lines of the motor, and means for determining the direction of rotation associated with an external control of rotation of the motor. in a given direction, depending on the absence or the presence of the phase shift when the engine is kept in the off position by the means of switching on or off.

  In an alternative embodiment, the device comprises a single means for accumulating and restoring the electric charge of supply, located on the supply line.

  Preferably, this means for accumulating and restoring the electric supply charge comprises a single supply capacitor.

  In another variant embodiment, possibly in combination with the previous embodiment, the device comprises a single sensor for the direction of rotation of the motor.

  Preferably, this sensor is a Hall effect sensor.

  In yet another embodiment, possibly in combination with any one of the preceding, the means for switching the engine on or off comprises a switch such as a relay, or a triac, or a power transistor.

  Preferably, the control unit comprises means for storing instructions and processing data and means for executing these instructions as a function of the processing data.

  The invention also relates, according to a second aspect, to a method for controlling a two-winding asynchronous motor, in particular an electronic end-of-travel rolling shutter motor, in which an alternating voltage is applicable. respectively to the first and second windings respectively via first and second control lines respectively of a first and a second direction of rotation of the motor, said motor comprising a phase shift capacitor.

  The method is characterized in that it comprises at least one step of external control of the motor in a first direction, at least a first detection step, the motor being out of order, a phase difference between the voltages respectively measured at the first and second motor control lines, at least a first determination step, the motor being out of service, the first direction of rotation, depending on the presence or absence of the phase shift.

  Preferably, the method comprises a step of memorizing the first direction of rotation determined in the first determination step, in association with the external control of rotation.

  Also preferably, the method comprises at least a second detection step, the motor being in operation, a phase shift between the voltages respectively measured at the first and second control lines of the motor, at least a second determining step, the motor being in use, the direction of rotation of the motor, according to the sign of the phase shift.

  Optionally, the method comprises at least one step of comparing the direction of rotation determined in the second determining step with the first direction of rotation stored in the storing step.

  When the comparison step shows a difference, the method comprises a step of stopping the motor.

  Optionally, a counter is incremented as and when the rotation of the motor in a given direction and decremented as the rotation of the motor in the opposite direction of the given direction, and, when the comparison step shows a In contrast, the method comprises a step of inverting the incrementation in the decrementation or the decrementation in the incrementation of the counter.

  The invention also relates, according to a third aspect, to a method for controlling an asynchronous motor with two windings, in particular a cage-type rolling shutter motor with electronic limit switches, implemented by the device according to the first aspect of the invention.

  Finally, the invention also relates, in a fourth aspect, to a storage medium readable by a processing unit, on which is stored a sequence of instructions which, when executed by the processing unit, allows to it to implement the method according to the second or third aspect of the invention.

  Other characteristics and advantages of the invention will appear more clearly and completely on reading the following description of the preferred embodiments of the device and the implementation of the method, which are given as non-limiting examples and with reference to the following appended drawings.

  - Figure 1: schematically shows a control device 15 according to the prior art, Figure 2: schematically shows a control device according to the invention Figures 3a, 3b: schematically represent the signals at the respective inputs of the control unit, for controls in a first direction of rotation, the engine being out of service, - figures 4a, 4b: schematically represent the signals at the respective inputs of the control unit, for commands in a second direction of rotation, the engine being out of service FIGS. 5a and 5b show diagrammatically the signals at the respective inputs of the control unit for moving the motor in use in a first direction of rotation. FIGS. 6a and 6b show schematically the signals at the respective inputs of the control unit. control unit for moving the motor in use in a second direction of rotation.

  Figure 1 shows schematically a control device according to the prior art and has been described previously.

  FIG. 2 diagrammatically represents a control device according to the invention.

  We thus find the 1: 3 motor with two windings 1 and 2, and a capacitor 3 of phase shift. The winding 1 and controlled by the control line 5 during manual control in the direction 1 (switch 21 in position 5), and the winding 2 is controlled by the control line 6 during a manual control in direction 2 (switch 21 in position 6).

  The voltages applicable respectively between these lines 5 and 6 of control and the neutral line 11 connected to the motor 13, are respectively delivered to the inputs 10 and 9 of a control unit 12.

  This control unit 12 may for example be a conventional central processing unit or CPU, with means for storing instructions and processing data and means for executing these instructions as a function of the processing data, such as a ROM and / or a RAM and / or an EEPROM.

  This control unit 12 controls a means 8 for switching the motor 13 on or off, situated between this motor 13 and the neutral line 11. This means 8 for turning the motor 13 on or off, or switch 8, can be for example a relay, or a triac, or a power transistor.

  Furthermore, the control unit 12 is powered by a supply means 7 whose input is connected, via a supply line 14, to only one of the control lines 5 or 6, the occurrence in Figure 2 at line 6.

  On the supply line 14 is located a unique means 4 for accumulating and restoring the electric supply charge, which corresponds to a means of extracting the voltage between the points 6 and 11 to provide the power supply to the control electronics. This is for example a capacitor 4.

  Optionally, a single sensor 15, for example of Hall effect type, is connected to the control unit 12.

  In contrast to the usual designs, the device is thus architected in such a way that the phase shifting capacitor 3 and the two windings 1 and 2 are elements which take an integral part in the operation of the device, in the same way in particular as the power supply capacitor 4. . Thus, the device exploits the presence of these elements to differentiate orders as well, to supply the control electronics, as to inform the control unit on the direction of rotation of the motor in association with the other elements of the device.

  The power supply of the device is now explained.

  In the case of manual external control in a first direction of rotation, via the control line 6, switch 8 is open, ie the motor is out of operation, the power is supplied directly via the supply chain 7.

  The capacity of the capacitor 4 is calculated so that the current flowing through it is at least equal to the minimum current required to power the control unit 12. The capacity of the capacitor 4 is therefore lower as the current consumed by the control unit 12 is low.

  During external manual control in a second direction of rotation, by the control line 5, switch 8 open, so engine out of service, the power is then through the supply chain 7 and the capacitor 3 phase shift which is placed in parallel with the two windings 1 and 2 of the motor 13.

  The current consumed by the control unit 12 being negligible with respect to the impedance of the windings 1 and 2 and the capacitor 3 of the motor 13, the voltage drop caused by these remains reasonable. c $

  When the switch 8 is closed, so the engine running (the engine is running), it is the phase-shifted voltage with respect to the winding 1 that is found across the winding 2, which feeds the unit 12 control.

  FIGS. 3a and 3b show schematically the signals at the respective inputs 10 and 9 of the control unit 12, for commands in a first direction of rotation, the motor 13 being out of service.

  Figures 4a, 4b show schematically the signals at the respective inputs 10 and 9 of the control unit 12, for commands in a second direction of rotation, the motor 13 being out of service.

  The determination of the direction of the commands by the control unit 12, switch 8 open, thus engine out of service, will now be described with reference to these figures 3a, 3b, 4a and 4b.

  During an external manual control in a first direction of rotation via the line 6, and as soon as the electronics are powered, the respective forms of the signal on the inputs 10 (FIG. 3a) and 9 (FIG. 3b) of the control unit 12 are observed. It can thus be seen that the two signals are identical since the same voltage is applied to the control line 5 and the control line 6, thanks to the capacitor 3 in parallel with the sky windings 1 and 2 of the motor 13.

  The control unit 12, noting the identity of the two signals, 25 therefore recognizes and stores a command in the first direction of rotation.

  During manual external control in a second direction of rotation via line 5, and as soon as the electronics are powered, the respective shapes of the signal on the inputs 10 (FIG. 4a) and 9 (FIG. 4b) of the control unit 12 are observed. Since a portion of the feed stream passes through the capacitor 3, this results in a slight phase shift d of the voltage at the input 9 of the control unit 12 (FIG. 4b).

  The control unit 12, noting the presence of the phase shift d, thus easily recognizes and stores a command in the second direction of rotation.

  Figures 5a, 5b show schematically the signals at the respective inputs 10 and 9 of the control unit 12, for a displacement of the motor in operation in a first direction of rotation.

  FIGS. 6a and 6b show schematically the signals at the respective inputs 10 and 9 of the control unit 12, for a displacement of the motor in service in a second direction of rotation. The control management, switch 8 closed, thus the motor in use, will now be explained, with reference to these Figures 5a, 5b, 6a and 6b.

  As soon as the direction is determined, the control unit 12 can authorize or not the rotation of the motor 13 by closing or opening the switch 8.

  The control unit 12 can observe, when the switch 8 is closed, through its inputs 9 and 10, that the motor rotates in the right direction. Indeed, when the motor is powered, there is, at the terminals of the capacitor 3 a strong phase shift of, much greater than d. This phase shift at a sign different from one direction of rotation to another, if one always takes the same point of reference.

  FIGS. 5a and 5b thus show a positive phase shift between the signal detected at the input 10 and the signal detected at the input 9 of the control unit 12, when the motor is rotating in a first direction of rotation.

  Figures 6a and 6b show a negative phase shift between the signal detected at the input 10 and the signal detected at the input 9 of the control unit 12, when the motor rotates in the second direction of rotation .

  The control unit 12 can thus determine whether the direction of rotation corresponds to the previously stored commands. Indeed, if a sudden inversion of control occurs when the motor 13 rotates, the phase shift of will be reversed, and the control unit 12 can implement a procedure which consists for example of stopping the motor 13.

  Optionally, the control unit 12 may comprise a counter which is incremented as and when the motor 13 is rotated in a given direction and decremented as the motor 13 is rotated in the opposite direction.

  If therefore the control unit 12 has such a counter, it can note the change of sign of the phase shift when a sudden inversion of control while the motor 13 rotates, and reverse the counting direction. Thus, if the direction of the count before the sudden inversion of control corresponds to an incrementation of the counter, this counting direction becomes a decrementation after this inversion. Otherwise, that is to say if the direction of the count before the sudden inversion of control corresponds to a decrementation of the counter, this counting direction becomes an incrementation after this inversion.

  Thus, the device, further provided with a single sensor 15 of Hall effect type, and the control method of the invention advantageously allow to monitor the speed of the engine and manage the stop at the end of the race.

  The whole of the description above is given by way of example, and is not limiting of the invention.

Claims (15)

  1. Control device for asynchronous motor (13) with two windings (1, 2), in particular for an electronic end-of-travel rolling shutter motor, in which an alternating voltage is applicable respectively to said first and second windings (1). , 2) respectively via a first and a second control line (5, 6) respectively of a first and a second direction of rotation of said motor (13), said motor (13) comprising a phase-shifting capacitor (3), said device comprising means (8) for switching said motor (13) between said motor (13) and the neutral line (11) on or off, and a unit (12) for controlling said means (8) for switching said motor (13) on or off, characterized in that said control unit (12) is electrically powered by a power supply means (7) whose input is connected, by via a feed line (14) to a single one of said first or second lines (5,6) for controlling said motor (13).   2. Device according to claim 1, characterized in that said control unit (12) comprises: means for detecting a phase shift (d) between the voltages respectively measured at said first and second control lines (5, 6). said motor (13), means for determining the direction of rotation associated with an external control of rotation of said motor (13) in a given direction, as a function of the absence or the presence of said phase shift (d) when said motor ( 13) is held in the off position by said means (8) for switching on or off.   3. Device according to any one of claims 1 and 2, characterized in that it comprises a means (4) for accumulation and return of the electrical supply charge, located on said supply line. (14).   4. Device according to claim 3, characterized in that said means (4) for accumulating and returning the electrical supply charge comprises a single supply capacitor.   5. Device according to any one of claims 1 to 4, characterized in that it comprises a single sensor (15) of the direction of rotation of said motor (13).   6. Device according to claim 5, characterized in that said sensor (15) is a Hall effect sensor.   7. Device according to any one of claims 1 to 6, characterized in that said means (8) for switching on or off said motor (13) comprises a relay, or a triac, or a power transistor.   8. Device according to any one of claims 1 to 7, characterized in that said control unit (12) comprises means for storing instructions and processing data and means for executing said instructions according to said data. treatment.   9. A method of controlling an asynchronous motor (13) with two windings (1, 2), in particular an electronic end-of-travel rolling shutter motor, in which an alternating voltage is applicable respectively to said first and second windings (1, 2) respectively via first and second control lines (5, 6) respectively of a first and a second direction of rotation of said motor (13), said motor (13) comprising a capacitor (3) of phase shift, characterized in that it comprises: - at least one external control step of said motor (13) 19.   in a first direction, - at least a first detection step, said motor (13) being out of operation, a phase shift (d) between the voltages respectively measured at said first and second control lines (5, 6) of said motor ( 13), - at least a first determining step, said motor (13) being out of service, said first direction of rotation, depending on the presence or absence of said phase shift (d).   10. Method according to claim 9, characterized in that it comprises a step of storing said first direction of rotation determined at said first determination step, in association with said external control rotation.   11. The method of claim 10, characterized in that it comprises: at least a second detection step, said motor (13) being in service, a phase shift (d ') between the voltages respectively measured at said first and second control lines (5, 6) of said motor (13), - at least a second determining step, said motor (13) being in use, of the direction of rotation of said motor (13), as a function of the sign of said phase shift (d). ').   13. The method of claim 11, characterized in that it comprises at least one step of comparing said direction of rotation determined at said second determination step with said first direction of rotation stored at said storing step.   14. The method of claim 12, characterized in that it comprises, when said comparison step shows a difference, a step of stopping said motor (13).   15. Method according to any one of claims 12 and 13, wherein a counter is incremented as and when the rotation of said motor (13) in a given direction and decremented as and rotation of said motor ( 13) in the opposite direction to said given direction, characterized in that it comprises, when said comparing step shows a difference, a step of inverting the incrementation in decrementation or decrementing in incrementation of said counter.   15. A method of controlling an asynchronous motor (13) with two windings (1, 2), in particular of an electronic travel-cage rolling shutter motor, implemented by the device according to any one of Claims 1 to 8.   16. A storage medium readable by a processing unit, on which is stored a sequence of instructions which, when executed by said processing unit, allows it to implement the method according to any one of the following: Claims 9 to 15.